Bone morphogenetic protein 2 gene transduction enhances the osteogenic potential of human urine-derived stem cells.

INTRODUCTION: Urine-derived stem cells (USCs) have the ability to differentiate into osteogenic lineage. Previous studies have raised the possibility that USCs could be used for bone repair. To harness the power of USCs in promoting bone regeneration, methods must be developed to induce USCs to osteogenic lineage efficiently. The present study investigates the effect of lentivirus-encoded bone morphogenetic protein 2 (BMP2) gene transduction on the osteogenic potential of USCs. METHODS: USCs were isolated from voided urine and transduced with Lentiviral vector encoding BMP2. An in vitro study was performed to detect Lentiviral-BMP2 transduced USCs differentiated towards osteogenic lineage. Furthermore, Lentiviral-BMP2 transduced USCs were transplanted in vivo to examine the ectopic bone formation ability. After six weeks, retrieval samples were obtained for immunostaining and histological analysis. RESULTS: The results showed that the transduction efficiencies were over 90%, and transduced USCs had high expression levels of the BMP2 gene and secreted BMP2 protein. Alkaline activity and mineral deposition staining demonstrated that transduced USCs differentiate into osteogenic lineages without the addition of osteogenic supplements. Transduced USCs also showed high expression of bone-related markers, including runt-related protein-2 (Runx2) and osteocalcin (OCN), confirming this lentiviral-BMP2 construct provides sufficient stimuli for osteogenic differentiation. Histological analysis indicated that the transduced USCs induced robust new bone formation in nude mice. Six weeks after transplantation, human derived cells were observed to participate in bone formation. CONCLUSIONS: These results demonstrate that BMP2 gene transduction provides an effective method to enhance the osteogenic potential of USCs.

Classification of gluteal muscle contracture in children and outcome of different treatments.

BACKGROUND: Gluteal muscle contracture (GMC) is a clinical syndrome due to multiple etiologies in which hip movements may be severely limited. The aim of this study was to propose a detailed classification of GMC and evaluate the statistical association between outcomes of different management and patient conditions. METHODS: One hundred fifty-eight patients, who were treated between January 1995 and December 2004, were reviewed at a mean duration of follow-up of 4.8 years. Statistical analyses were performed using X2 and Fisher's exact tests. RESULTS: Non-operative management (NOM), as a primary treatment, was effective in 19 of 49 patients (38.8%), while operative management was effective in all 129 patients, with an excellence rating of 83.7% (108/129). The outcome of NOM in level I patients was significantly higher than in level II and III patients (P < 0.05). The results of NOM and operative management in the child group were better than the adolescent group (P < 0.05). Complications in level III were more than in level II. CONCLUSION: NOM was more effective in level I patients than in level II and III patients. Operative management was effective in patients at all levels, with no statistical differences between levels or types. We recommend NOM as primary treatment for level I patients and operative management for level II and III patients. Either NOM or operative management should be carried out as early as possible.